Hello!Everyone.

I have 2 computers but only a monitor.I want to control Computer B via Computer A,this scenario will make you envision using putty or VNC software.However,computer B does not have X Window,which will increase the consumption of memory.So,how can I connect to Computer B just like sitting in front its screen?

Why do I want to do this?Because I want to backup Computer B using PartImage (Bootdisc).I don't want to unplug the monitor of Computer A for Computer B.Worse still,I have to go back and forth if there are any problems of Computer B.

Do you guys have any suggestions?I hope the software will make me know what's the screenshot if I pop in the Bootdisc in Computer B and get control over it.

have X installed on computer B. VNC will create a X session that uses little amount of memory. you can also ssh tunnel with VNC. not sure what advantages TightVNC had just use regular VNC myself.

you will need a window manager also.

If you don't have X installed on Computer B, then just use ssh

VNC of whatever variety (Tight/Real/x11vnc/etc) will rely on the server PC (computerB) having X installed and being stable enough to run it.

You will only get access through VNC once computerB has booted into run level 4.

If you want to look at boot messages and other items as tho' you were sitting at computerB, then you require a KVM switch!

Good luck!
- Piete.

Thanks for the quick replies from you guys!

piete,what is KVM switch?I don't know is there any misunderstanding of what I want.I would like to know what's happening to the screen when I pop in the bootdisc in the server remotely.In my case,I would like to know the screen after I pop in PartImage software because I have to select the appropriate option.

Thanks for the replies again.

KVM is keyboard/video/mouse. It's a switch that allows you to use one monitor, mouse, and keyboard with two or more computers. Some use a push-button mechanism while other use a key on the keyboard to change computers. The one I have cost about $30US.

Kent

VNC will only work if the system you want to look at (ie: computerB) is running the VNC server. VNC server runs after the OS has booted.

Since you want to inspect the boot process itself (not some kind of log thereof) and require pre-OS access to the system, a KVM switch will let you connect one keyboard, monitor & mouse to two (or more) PCs. It's an external device.

As Kent as already mentioned, they're not too pricey and are pretty easy. Google for some pictures/prices and you'll hopefully understand what they do better.

You cannot do what you wish to do with software, I think.

- Piete.

Ever thought of connecting computers A and B with a null-modem serial cable and then redirecting console output to the serial console?
That way, you can watch the complete boot process of computer B in (for instance) a minicom screen on computer A.

Beats the price of a KVM... only, you cannot run X-Window on computer B that way and with a KVM switch you can.

Eric

VNC depends a lot on your NICs, but also a lot on the screen resolution you use. I run my boxes at 1280 x 1024. I'm using 10/100 NICs but screen response through VNC is sluggish at the high resolution. Yes, I could reduce screen resolution, but I won't. And my LCD monitor runs natively at 1280 x 1024.

I bought a KVM to resolve the basic problem of having only one good monitor. I did some research and eventually bought a IOGear GC612A. However, I recommend you get the next lower model that does not include the audio cables. The audio switching does not work and other people have confirmed likewise. Otherwise picture quality, and mouse and keyboard response are fine. I paid $56 street price. Toggling between the two boxes is a matter of pressing the Scroll Lock key twice in a reasonably rapid motion. I am satisfied with the KVM.

I'd like to use VNC more, but the screen resolutions I use probably will always discourage me from doing so. And my boxes probably are too old to support bleeding edge NICs. Possibly I don't have my NICs tuned properly. My unscientific measurements indicate a file transfer speed between my two boxes of approximately 32.4 Mbits per second (4.05 Mbytes). I probably should see higher numbers with 10/100 full duplex. However, for now the KVM resolves my need to run two boxes with one monitor, mouse, and keyboard.

I have configured basic networking, SSH, SCP, etc., and I can move files through the network rather than sneaker net. Works for me. Actually, this setup is a rather convenient method to run multiple boxes without the overhead of VNC. Of course, YMMV.

4.05 Mbits = 0.5 megabytes

Doh! Good eye! Got my numbers transposed while typing. Edited. Thank you!

Woodsman,thanks for your in-depth analysis.I have decided to buy a KVM.However,is your KVM device have 3 ports (1 for IO of monitor,the rest of ports are graphic cards' port)?Maybe I bought it wrong.I think there should be 2 more ports for keyboard and mouse.Is that right?

Thanks for the suggestions from you all.

A KVM should indeed have ports for mouse and keyboard (hence KVM = Keyboard/Video/Mouse), sounds like you've got a video switchbox. KVM switches look like this.

I think it's the best (easiest) solution for what you're trying to do.

A KVM will be mostly "spider legs." That is, for a 2-port KVM there will be nine cables. Three cables on one end of the KVM attach to the monitor, mouse, and keyboard. The other six connect to the two computers.

If you want to control three or more boxes then you will have to look at 4-port, 8-port, etc., KVMs.

If there are no cables then, as odevans mentioned, you might be looking at an old mechanical A/B switchbox. You do not want to use that box to switch your monitor because the old mechanical switches provide no amplification to offset the longer cable lengths being used. Because of the longer video cable lengths you also will experience signal reflections in the signal which on screen will look like ghosting on your TV.

The newer KVMs use digital circuitry to buffer the switching, amplify the signal, and simulate a keyboard and mouse attached for the computers that you are not viewing through the KVM. The latter is necessary to bypass the BIOS when you boot a box that you are not actually viewing. That is, if you are viewing Box 1 through the KVM, then the keyboard and mouse are live to Box 1 and during the boot Box 2 normally would see no keyboard. The KVM simulates the keyboard to avoid that problem.

I have older boxes and the KVM model I bought is for PS2 connectors. If you have a newer box you probably will want USB connectors. The video connector is the same standard 15-pin connector. If your monitor uses the newer digital connector then you'll have to shop accordingly.

Actually, I use a real keyboard---a 16 year-old Northgate Omnikey Ultra that I refuse to part with and that keyboard uses the old 5-pin DIN connector. But two PS2 converter adapters solved my problem, although the vendor says that 5-pin DIN is not supported. I needed one female-to-male converter to plug the keyboard into the KVM and one male-to-female to plug the KVM into the computer. Those kinds of situations mean scrapping through the old junk box, for sure!

FWIW, I also use a 6-foot extension cables on both the mouse and keyboard and I never have noticed any problems. Been using the extension cables for several years before buying the KVM.

Oh, BTW, many of the KVMs will provide an LED indicator so you can see which box is live. Some KVMs also provide audio beeps when switching and if you think you'll be switching often, then avoid buying one of those. When I'm playing with both boxes I am switching often and in hindsight any audio signal would have driven me nuts by now.

Lastly, I went the KVM route because for a long time I endured the multi-boot nonsense. I inherited an old second box and that became my dedicated Slack box to experiment and helped me greatly reduce my need to reboot the first box. The VNC idea certainly comes with a "cool" factor, but the KVM is more practical to me now that I have tried both methods. A nice advantage too is that when I first began testing SSH and SCP I actually had two physical boxes to toggle between and that realism helped.

If you remain uncertain, Google for the KVM model number I listed above and look at the pictures.

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Drool... I'm still banging away on a Dell keyb that's essentially a re-branded late model IBM Model M. Easy to disassemble and clean, and, man, just can't beat the buckling spring action and the click. And you just can't bang on or beat up new rubber-dome keybs the same way.

If / when it finally dies I'll be beating a swift passage to this place.

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